| 摘要 |
PROBLEM TO BE SOLVED: To reliably display the existence of a depression-shaped topographic part regardless of a viewpoint height of a display screen when a road map is three-dimensionally displayed together with topography. SOLUTION: On a three-dimensional display screen, the water surface of a river R1 located at a position where the angle of depressionθwith respect to a viewpoint EP is relatively large is displayed with light blue. About a river R2 located at a position where the angle of depressionθwith respect to the viewpoint EP is relatively small and its water surface is hidden by a display object (bank, etc.), on this side so as not to be shown, the bank BK2 on the opposite bank side that is shown on the screen is displayed while colored by light blue. A river R3 located at a position where the angle of depressionθwith respect to the viewpoint EP is small (far position) is two-dimensionally displayed. |
